Countries across Europe have suspended the Oxford/AstraZeneca Covid-19 vaccine over concerns the jab may cause blood clots, even though medicines regulators and the World Health Organization say there is no evidence of problems.

Germany, Italy, France, Spain and the Netherlands became the latest countries to pause the rollout of the jab on Monday. Norway, Denmark and Bulgaria suspended their programmes last week.

The suspensions came as the WHO urged nations not to pause Oxford/AstraZeneca inoculation programmes, having said last week there was no sign the problems had been caused by the jab. Boris Johnson, the UK prime minister, said Britain’s medicines regulator saw “no reason to discontinue” use of the vaccine, with Downing Street asserting that the jab was both “safe and effective”.